Seasonal Changes in the Aggregate Status of Particles in Dough used in the Manufacture of Insulators

Abstract

In order to clarify the mechanism of seasonal changes in agglomeration and dispersion of the slurry used in the manufacture of insulators, we focused our attention on the concentration of iron ions which elute within slurry, added water glass and long-term storage treatment to process slurry, ore slurry and clay slurry, carried out heating treatment, and then measured the concentration of the eluted iron ions. Furthermore, when we evaluated the variations in zeta potential and slurry fluidity, we discovered that there was an influence caused by slurry temperature during ore grinding. Slurry temperature during ore grinding can be 20°C or more warmer in the summer than in the winter. As a result, even greater amount of iron ions elute from the pottery stone. The elution of iron ions causes particles to acquire more negative charge, which causes stronger repulsion among particles. We learned that, during the summer months, when slurry is warmer and there is a great amount of eluted iron ions, slurry tends to disperse. Conversely, we also learned that in the winter months slurry tends to agglomerate.